ABSTRACT This study is related to the interest area outlined in PA-18-591, specifically, the expansion of projects to include work related to Alzheimer?s Disease and Related Dementias (ADRD). There is increasing evidence that Alzheimer?s disease and related dementias have their origins much earlier in the life course than when symptoms occur. An individual?s occupation and work life are often their longest and most frequent social exposures; risk factors that occur or cumulate during working years represent an important area of focus in understanding potential dementia prevention or intervention. Still, data limitations have rendered study difficult. The aim of this project is to use the rich administrative data available from the Alcoa cohort to examine occupational and individual risk factors and working conditions during midlife on the risk of Alzheimer?s disease and dementia in later-life. Specifically, we will explore four risk factors that occur and/or cumulate during working years: the role of depression and depressive symptoms; hearing impairment; chronic sleep deprivation, as measured by long working hours; and cumulative exposure to particulate matter. The detailed and longitudinal nature of these data?often spanning over a decade of a workers? tenure?represent a significant contribution to the efforts to understand the role of occupational risk factors to ADRD. This research will shed light on potentially modifiable risk factors of ADRD that occur in midlife and as a part of one?s occupational context. Given the importance of work and working conditions in shaping health, understanding the contribution of such factors offers new opportunities for prevention and intervention of ADRD.